用VS2005.NET进行三层结构应用程序的开发(2)

public abstract class Base
{
#region DataAgent
private DataAgent m_objDBAgent;
protected DataAgent OleDBAgent
{
get
{
if(this.m_objDBAgent == null)
{
this.m_objDBAgent = this.CreateAgent();
}
return this.m_objDBAgent;
}
set
{
this.m_objDBAgent = value;
}
}
#endregion DataAgent
public Base()
{
} 
#region CreateAgent
/// 

/// Create a new DataAgent
/// 

/// the DataAgent
private DataAgent CreateAgent()
{
string strConnection = 
ConfigurationSettings.AppSettings["ConnectionString"];
return new DataAgent(strConnection);
}
#endregion CreateAgent
} 

public class News: Base
{
public News Contact()
{
}
public DataView GetNewsList()
{
string strSql;
strSql = "";
strSql += "   SELECT Top 10 NewsId,NewsTitle ";
strSql += "     FROM Tb_News";
strSql += "    WHERE NewsEnable = 1";
strSql += " ORDER BY NewsId ";
return base.OleDBAgent.GetDataView(strSql);
}
}

      News objNews = new News();
this.dgNews.DataSource = objNews.GetNewsList();
this.dgNews.DataBind();